Signaling system



A. A. CLOKEY SIGNALING SYSTEM Filed Nov. 29. 1921 2 Sheets-Sheet l A, :21:1 WW

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A. A. cLoKEY SIGNALING SYSTEM File Nov. 29, 1921 2 Sheets-Sheet 2 'vEI-DDDEIEJ' HC umnuuuu u M (L m@ MUN-m /m/ew/or.'

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)rimmed Jan. i3, 1925.

UNHTE ALLISON A. CLOKEY, RUTHERFORD, NEW JERSEY, ASSIGNOR T0 WESTERN ELEC- TRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y.,` A CORPORATION 0F NEW Yonx.

SIGNALING SYSTEM.

Application filed November 29, 1921. Serial No. 518,571.

To all whom it may concern:

Be it known that I, ALLIsoN ANDREW CLoKnY, a citizen of the United States, residing at Rutherford, in the county of Bergen, State of New. Jersey, have invented.-

' lines, the signaling currents are so reduced in strength and distorted or altered in "wave form by the transmitting medium thatwith the customary voltages applied, perfect reception at high speeds is difficult. An arrangement for minimizing the effects of such distortion and loss of energy and which has been used successfully for a number of years on land lines and short submarine telegraph cables both in connection with manually op erated systems and multiplex printing telegraph systems, is known as the Gulstad vibrating relay. As ordinarily used, this type of relay consists of a polarized relay provided with three windings, which are termed line windings, opposing windings, and accelerating windings. The two latter windings are included in a vibrating circuit comprising a battery, the relay tongue and contacts and adjustable condenser and resistances. In practice, by adjustment of the resistances and condenser in the vibrating circuit, the relay tongue is caused to vibrate at a slightly greater frequency than the dot frequency transmitted from the distant station.

To obtain the best possible results with a relay of the type previously referred t0, it is necessary that the frequency of vibrations exactly correspondl to the frequency of the signals transmitted from the distant station,

and that the wave form of the vibrating current nearly coincide with the' wave form of the received signals, but. owing'to the effects of temperature. extraneous `disturbinvention is particularly adapted, although its use under other circumstances may be found advantageous.

Broadly considered, the invention contemplates a telegraph system employing an electro-responsive device, such as a relay, so constructed and arranged that the frequency of its vvibration is automatically maintained in synchronism with the transmitting and receiving mechanisms. Specifically, the present invention contemplates the provision of a vibrating relay arrangement in which the frequency of vibration thereof is under the control of the receiving distributor, which in turn.l as in standard multiplex printing telegraph systems, is automatically maintained in synchronism with the transmitting distributor.

In the accompanying drawing:

Fig. 1 illustrates an arrangement representing one embodiment of the invention;

Fig. 2 shows curves representing the currents in the various circuits of the arrangement shown in Fig. 1;

Fig. 3 showsy a modification of the arrangement disclosed in Fig. 1;

Fig. 4 illustrates the shape of the current waves in the circuits of Fig. 3.

In Fig. 1 a cable 10 extending from a distant station and terminating at station X is shown connected in series with a receiving condenser 11 shunted by a resistance 12 or other form of distortion correcting network and the input circuit of a vacuum tube or other type of amplifier. To the output circuit of the amplifier there is connected the 'main or holding winding 14 of a vibrating relayl V13. A vibrating winding 15 has one terminal connected to ground,` while the other terminal is connected with the continuous ring 22 of a rotary receiving distributor 38.-

The receiving distributor 38, which for the sake of clearness has been shown developed, comprises three sections; E,y F, and G, each of which consists of a continuous ring and a second ring divided into segments which are adapted to, be bridged b a brush individual to each' section. Eac brushes 19, 20 and 21 is secured to an arm 18,

'arranged to be continuously rotated; by

means of a motor (not shown). Ring 23 numbered segments.. thereof connected toofthe l `forming a part of the section E has the even :i

etc. of 4' ring 25 in section F, and the two min'al of a condenser 35, which has its other terminal connected to ground. The odd l numbered segments of ring `23 are connected n together, and to the group of segments 4, 8,

12, etc. of'ring 25 which are connected to a condenser 36, which like condenser 35, has one terminal grounded. 'The segments of ring 27 are connected to the selecting mag- Irets of a 'receiving printer diagrammatically represented by the rectangle ,28.

, The operation4 of the arrangement'shown in Fig. 1 is as follows:

' When no current is flowing through the vmain or holding Windin'g1'4 of the vibrating relay 13, the passage of the brush over the segment causes condenser 36 to be negatively chargedvover a circuit extending from battery 16, armature of relay 13,ring 24, brush 20segment 40to the terminal of the condenser 36. As this same brush be- ,gins to pass over segment 1, the charging circuit for the condenser is opened, and the brush 19, Vwhich bridges the rings 22 and 23,

connects the condenser 36 with the vibrating winding 15 of the relay 13. This circuit may be traced from the condenser 36,' segmentl of the ring 23, brush 19, ring 22, resistance 34 and the two windings formin the vibrating Winding in series to `groun The condenser 36 is thereby discharged through the vibrating winding 15 in a direction so Vthat the armature of the relay 13 is caused to reverse its position, that is, to transfer the circuit extending from the negative terminal of battery 16 to the positive terminal Lof the battery 17 The .battery 17 is now connected t by meansof the brush 20upon the passage Vso "segments to whi thereof over segment 2 of the ring 25 with the condenser 35, which is thereupon charged ositively with respect to ground. As the -rush 2O is lpassing over segment 3 of the ring 25, the brush 19 is at this instance passing over segment-2 of the ring 2 3, and since the segment 3 of the ring 25 is an open segment, a discharge circuit is established for the condenser 35 ina manner similar to that described for the condenser 36. The discharge of the condenser 35 through the vilbratlng windi g 15 is in a direction such as to reverse the position ofthe amature to lts original position, or the -position shown in the drawing. .Thus, as the brushes pass `over the respective segments of the sections E and 1V, the condensers 35 and 36 will be alternately charged and discharged in a manner such as to cause the armature of the elay lllto'vibrate betweei its two cgnttzcts or a in negative an positive a ery to thgliixyig gli of the section G. Each time the armature opens and closes its contact due to the passa -of the -bru,h.21 over the the selecting magnets29, 30, 31, 32' and 33 of the printer mechanism 28, an energizin circuit is established for the respective selecting magnets, depending of course upon the position of the armature of the relay 13. l

The frequency at which the armature vibrates, however, depends only on the number -of segmentsA employed and the' speed of roltation of the brushes.

Assuming now that a signal of a negative Apolarity and of sufficient 'duration lis impressed 'at the opposite-end of the cable 10 to cause the current in the main or holding winding 1:4 at the time the brush 19 is passing fromsegment 1` of the ring'23 and on to segment 2 of this ring, lto be 1n a direction opposite to the current in the vibrating winding produced by the discharge of the condenser 35 `and to be of a strength suiicient to neutralize the effect of the vibrating current thus preventing the armature of the relay 13 from leaving the negative'terminal ofthe battery 16, during theJ passage of the vbrush 19 over segment 2. If the received signal diminishes to 'a small enough value during this time. the armature ofthe relay 13 will move to the positive contact terminal ofthe battery 17 when 4brush 19 passes over segment 3 of the ring 23 owing to the act that the condenser 36 was charged negatively by the passage of the brush 20 over segment 4 of the ring 25. If the value'of the received signal current impulse doesnot diminish during the time that the brush 19 is passing over segment 2 of the ring 23 or succeeding segments thereof, the armature ofthe relay 13 will continue to remain in ,'ntact with the negative terminals of the battery 17junti1 suclt time as thesignaling current through the main or holding winding 14 diminishes to a value whereby the current through the vibrating winding 15 predominates, and thereby causes the reversal of the position of the armature. The wave form and magnitude of the current in the vibrating winding 15 of the 'relay may becontrolled by varying the value of the 'resistance 34 and the capacities of the con? densers 35 and 36. Also if it is desiredtoA reduce the rate at which current rises in the vibrating winding15, a condenser of the shunted about the at the'distant endv of the 21 over the segments of the ring 27 of the section G of the distributor, a circuit is established for the'selecting magnets of the receiving'printer,l which will respond depending upon the polarity ot the battery applied to its Corresponding segment. Thus if the current in the main or holding winding 14 is of a value too low to prevent thevibration of the armature of the relay 13, each of the selecting` magnets will be energized in accordance with the polarity of the battery with which thearmature is in engagement at the instant the brush 2l is passing over the segments of ring 2T to which the selecting magnets are connected.

In Fig. 2 there is shown a series of curves representing the characteristics of the currents in the various circuits of the arrange ment shown in Fig. l., and which illustrate the proper wave shape and phase relation of the vibrating and holding currents necessary to produce satisfactory operation of the relay arrangement described in connection with the previously mentioned figure.v

In this ligure A represents the current impulses impressed upon the line at the distant station. the set of'curves B represents the currents in the main and vibrating windings of the receiving relay, curve C represents the effect of the set of curves B. in energizing the line relay at the receiving station, and curve D represents the signals as relayed to the recording instrument. The dotted lines of curve C shows the effeet upon the energization of the relay which would be caused by a change in Ywave .form orAphase displacement of the vibrating windings -as represented by the dotted lines in the set of curves B, and the broken lines M and N represent respectively the minimum value of positive and negative current necessary to operate the relay.

Assuming now that the shaping'network at kthe receiving .end of the cable is such as to produce signals 'of the shape shown at O', and the current in the vibrating winding is Vas shown at II in the set of curves B if Fig. 2, then the total current acting upon the relay to produce operation thereof will be thealgebraic sum of those two currents, which is'- illustrated by the curve C. The relay operated by this current will repeat into the local receiving circuit sigwas originally the case.

nals exactly the same as originally transmitted, as are represented by the curve lA. It', however` the wave shape of the vibrating current H should be altered to the form shown at f, the addition to it of the line current would cause the effective current acting upon the relay to increase, as shown at d of curve C, instead of falling o as thereuponoperate at the instant. the current reacfiesthe value f 'somewhat earlier than it otherwisejwould, and the signal,

The relay wouldv which was being repeated in the local circuit would be considerably shortened thereby, While the succeeding impulse would consequently be lengthened.v If the vibrating current were made vto rise as inthe case of the Gulstad relay, instead of falling off, as previously referred to, this distortion would become more objectionable, and operation of the relay would be impossible. If the phase of the vibrating current with respect to the holding current should be shifted so that afreversal of the former occurs atA a.. the effect would be to reduce the value of the operating current to that shown at a, which is so little in excess of the minimum value of the positive impulse required to operate the relay,.that unsatisfactory operation would result. Again if the phase of the vibrating current should be shifted in a direction opposite to that just described, the same effect would be obtained. However, if the received signal current impulses were of different shape than shown, it would also be necessary to alter the shape of the vibrating current. Thebest wave shape can be easily determined by determining the characteristic of the relayedvsignal while the adjustment of the condensers 35 and 36 and the resistanceis being made. The proper phase relation of the respective .signal may be obtained by orienting the brushes of the distributor which control the connection of the condensers with the vibrating Winding V15 of the relay.v n

When the relay arrangement responds to a long signal resulting from the transmission of a series of, impulses of the same polarity, the algebraic sum of the curves H and O as shown at d2 reachesia value almost suliicient to cause the relay to reverse the position of its armature at a time when no reversal should take place. No change which it is possible to make in the shape of either the vibrating or holding` current will overcome this condition without introducing other equally undesirable conditions. However` by using only a por; tion ofthe received signal, as will be hereinafter described, the current in the holding winding will be nearly square-topped as shown in the shaded portions of B Aor Fig. `4. With the arrangement described in connection with Fig. l, a signal relayed to the receiving printer will'be similar to the'cur've Dzof Fig. 2, and Jwhich is similar,

to the transmitted signal current Wave as v shown in A of this figure'.

Fig.v l, the cable 50 has'in seriesitgfierewith ra receiving condenser 51 shunted 'by a resistance 52, or other distortion correcting network, but the output circuit of the amplificr is connected in series with the main or holding winding 55 of the rclay 70, the connection of which is controlled by brush 63 of the receiving distributor. With the arrangement illustrated in this Vgure, the receiving distributor is vprovided with two sections, K'and P. The former comprises a continuous ring 66 and a segmented rin@ 67, which controls the charging and disciarging of a condenser 65. The section P comprises a continuous ring 68 and a segmented ring 69, certain segments of which are connected with the holding winding 55 of the relay-70, thereby controlling the connection of this winding in circuit with the cable 50. The ring 67 of the section K has the segmentsI thereof so arranged that the length of each segment is one-sixth of the length L of a sending segment of the distributor at the distant end 'of the cable. The length of the segment of ring 69 is equal to one-third the length of the sending segment. Only the center segment of each group of three segments of the section P is connected to the holding winding 55 of the vibrating relay 70, thus causing the cable to be connected to the vibrating relay during only one-third of a complete signal interval, whereby only a portion of the received signal will be effective on the main line winding. The connections to each group of such'segments in the section K are such that as .the brush 62 passes over the first or No. 4 segment, the condenser 65 is charged. vThe second segment, No. 5, is opened, the third and fourth segments, ,6 and 7 which correspond in position to the center or live lsegment of each groupl in the section P cause they condenser 65 to discharge through Vthe vibrating Winding 56 of the vibrating relay 70 in a manner similar to that described in connection 'with Fig. 1, but which will be simultaneous with the association of the winding 55 with thecable 50. The fifth segment, No. 8, upon the passage of the brush 62 thereover, short circuits .the con-f denser 65 and reducesthe residual charge therein to zero. Thus at the instant the brush 62 passes on to segments Nos. 6 and 7, it thereby causes the condenser 65 to discharge through the vibratin Winding -56 of the vibrating relay 70. The simultaneous passage of the brush 63 on to segment No. '4 of the rin 69 causes the output circuit of the ampli er to be connected to the holding; winding 55, and if the current in the latter winding is of the required value and lopposite in direction tothe vibrating current' during the time the brush 62 is passing over the corresponding segment, theV reversal of the armature of the relay, which wouldv otherwise occur at that time, will be pre?i vented andcannot occur until the corre` spending time in the next signaling interval.

This reversal will then occur only in case' the current inthe main or'holding winding 55 is too low to predominate the effect of the current in the vibrating Winding 56.

In order to simplify the arrangement, the recorder 60 is shown permanently connected to the armature of the vibrating relay.

The wave shape and amplitude of thel vibrating 'current may be adjusted as desired by varying the resistances 57l and 71 and the capacity of the-condenser 65.

In Fig. 4 the curves A, B, C and D represent the currents utilized in an arrangement of the character disclosed in Fig. 3. Curve A represents signals as transmitted from the distant end of the cable 50, the curve B representsthe received signals, the shaded portionsV of which represent the part of the signal which is caused to act on thel holding or main line winding 55 of the vibrating relay 7 0. Curve C represents the current in the vibrating winding 56 as selected by the arrangement of the segments of the distributor as previously described, while D represents the algebraic sum of the current shown in C and the shaded portions of B. When the current in the vibrating Winding is approximately square.

topped, the currenty acting upon the relay to operate it will also approximate squa'retopped pulses, and those pulses occurring.

during the intervals when the relay armature remains in contact with either of itsv opposing contacts, will be much smaller in value than inthe method utilizing a'll of the received signal. It should be noted that due td the fact that the line or cable is disconnected from the receiving a paratus during two-thirds of each signa period, the receiver will not be affectedl by disturbances occurring during that time, and the number of errors from this source will therefore be materially reduced. The rectangles appearing just below the cross-sectioned part of the curve B represent the segments of the distributor section K which receive only a portion of the received signal current wave, thus relaying into the receiving or local circuit a signal wave substantially like the one disclosed at A of Fig. 4.

It is apparent from the previous descrip# tion that the present invention provides 'a system in which, due to the attenuation of the cable, signals of a frequency equal to or greater thanthe dot frequency will lhave no-appreciable-,effectson the receiving relay,

receiving synchronous distributors.A Howeverewhen signals of a llov'ver frequency are received, the current in the main line windpredommates the current in the vibrating winding and prevents the vibration of the armature until suchtime as the current inthe main line winding has changed suiliciently so that it no longer predominates.

What is claimed is:

l. In a telegraph system, the combination of an incoming ltransmission line, and a relay comprising a line winding, an armature, current supply contacts cooperating there- 1o with, a local circuit winding arranged to produce a magnetic eect on said armature Vsuiicient to cause the movement thereof,

current supply means for said local circuit Winding, and synchronously operated means 16 for rendering said current su ply means and said local circuit winding e ective in an invariable phase relation with the transmitted signals for causing the reversal of said armature.

2. In combination with a telegraph system, a receiving relayv comprising a line winding, an armature, current supply contacts co-operating therewith, a local circuit winding arranged to produce a magnetic effeetA on said armature sulicient to cause the movement thereof, electrostatic means serving upon the discharge thereof to supply current to said local circuit winding, and

means synchronously operated in an invariable phase relation with the transmitted signals for permitting the discharge of said electrostatic means through said local circuit winding.

3. In a telegraph system, the combination 85 of an incoming transmission line and a relay comprising a line winding, an armature current supply contacts cooperating therewith,

a local circuit winding arranged to prod uce a magnetic effect on said armature sufficient to cause the movement thereof, means serv- Y ing to supply current to said local circuit winding, and a syuchrononous rotary distributor for rendering said means eiective on said local circuit winding.

4. In combination 'with a'telegraph system, a receiv-ing relay comprising al line Winding, an armature, current supply contacts cooperating therewith, a local circuit Winding arranged Ato produce a magnetic effect on said armature suiicient to cause the movement thereof, current supply means for said local circuit winding, synchronously operated means for rendering said current supply means and said local circuit winding effective in an invariable phase relation with the 'transmitted signals for causing the re- `versal of said armature, and recording means responsive to the reversal of the armature of said relay.

5. In combination with a telegraph system, @receiving relay comprising' a line winding, an armature, current supply contacts cooperating therewith, local circuit electromagnetic means arranged to produce a magnetic effect on said armature suicient to cause the movement thereof, a condenser serving upon the discharge thereof to energize said local circuit electromagnetic means, a synchronous rotary distributor for controlling the charging of said condenser and the completion of a discharge circuit therefor including said local circuit electromagnetic means.

6. In combination with a. Itelegraph sys'- tem, a receiving relay comprising a line Winding, an armature, current supply contacts cooperating therewith, a local circuit winding arranged to produce a magnetic eii'ect on said armature sutlicient to cause the reversal thereof, means serving to supply current to said local circuit winding, and a synchronously operated rotary distributor for rendering said means and said local circuit winding effective on said armature during onlya portion. of the total signal` interval.

7. In combination with a telegraph system, a relay comprising aline Winding, an armature, current sup-ply contacts cooperating therewith.l a local circuit Winding arranged to produce a magnetic eliect on said varmature sufficient to `cause the reversal thereof, a. condenser'serving upon the discharge thereof to supply current to said local circuit winding, and synchronously operated means for establishing a discharge circuit for said condenser extending through said local circuit winding during only the central portion of the total signal interval.

S. In a telegraph system,vthe combination of an incoming transmission line and a relay comprising a line winding, an armature, current supplx7 contacts cooperating therewith, a local circuit winding arranged to produce a magnetieeffect on said armature sufficient to cause the reversal thereof, a condenser serving upon the disch-arge thereof to supply current. to said local circuit winding, and a synchronous rotary distributor having the segments thereof so connected that a discharge circuit for said condenser is established through said local circuit winding during only a portion of the total signal interval whereby the central portion of the signal wave is relayed into the local circuit.

9. A polarized relay comprising a movmain circuit electromagnetic means arranged -to influence said armature, local circuit electromagnetic means also arranged to inuence the movement of said armature, current supply means for said local circuit electromagnetic means, and means synchronous with the transmitted signals but independent of said armature for establishing 4an operative connectionbetween said current supply means and said local circuit electromagnetic means for effecting the reversal of saidarmature.

10. A polarized relay comprising a movable armature, opposing contacts therefor, i

able armature, opposing contacts therefor, main circuit electromagnetic means arranged to influence said armature, local -circuit elec-y tromagnetic means also arranged to influence the movement of ysaid armature, a coiidenser for supplying current to said local circuit electromagnetic means, and means synchronous with the impulses received over the main circuit and independent. of said armature for establishing a discharge circuit :t'or said condenser through said local circuit electromagnetic means whereby said armature is caused to reverse its position upon a diminution of the current in the main circuit electromagnetic means. y

l1. The method of-signaling over cables in which signals of dot frequency' are so attenuated to practically disappear atthe receiving station, which method consists in supplying to the vibrating winding of the receiving line relay local impulses which are in synchi'onisni with the distant transmitter, and altering the sequence of such vibrating im ulses by means of signals received over the line which are too small to directly produce operation of the receiving relay.

12. In a telegraph system, the vcombination of a transmission line, a receiving relay comprising an armature, opposing contacts therefor, main circuit electromagnetic. means arranged to influence the movement of said armature, local circuit electromagnetic means likewise arranged -to iniiuence the `movement of said armature, synchronously operated means for associating said main circuit electromagnetic means with said line during onlyV a portion of the total signal interval and current supply means rendered effective on said local circuit electromagnetic means simultaneouslywith the association of ',said main circuit eleetrmagnetic means with said line.

13. In combination with a line circuit, a

corresponding signal indications in said local circuit.

14. In combination with a line circuit, a

signal receiving relayl a local circuit controlled thereby, -a loca interrupter for supplying periodic impulses in an invariable order to said relay and thereby to cause the vibration of the armature thereof, and circuit connections wherebyl signal impulses received over said line circuit are caused t`o aid or oppose said periodic impulses and thereby to give corresponding signal indications in said local circuit.

15. In combination with a line circuit, a signal receiving relay, a local circuit controlled thereby, a rotary distributor for supplying periodic impulses to said relay, and

circuit .connections whereby signal impulses lreceived over said line circuit are caused to aid or oppose said periodic impulses andv thereby to give corresponding signal indi-l cations in said local circuit.

16. In combination with a line circuit, a signal receiving' relay, a local circuit controlled thereby, a continuously rotating distributor for supplying periodic impulses toA saidrelay, and circuit connections whereby signal impulses received over said line circuit are caused to aid or oppose said periodic impulses and thereby to, give corresponding signal indications in said local circuit.

' Inwitnes's whereof, I hereunto subscribe :ilny name this\22nd day of November A. D.,

ALLisoN A. oLoKEY. 

